1. Field of the Invention
This invention is directed to an apparatus and to a method for use in laproscopic surgery. More specifically, this invention concerns an improved composite suction/irrigation probe for use in conjunction with a hydrodissection apparatus, and to a method involving concurrent infusion and suction of hydrodissection fluid.
2. Description of the Prior Art
Hydrodissection procedures typically involve directing a pressurized fluid stream at a target tissue through a probe, followed thereafter by suction of the fluid from the operative field through the same probe; or, through a probe connected to a separate instrument. This procedure, as practiced with a symmetrical valve (i.e. trumpet valve) of the type disclosed in the U.S. application Ser. No. 07/470,771 filed on Jan. 26, 1990, now issued as U.S. Pat. No. 5,188,591 on Feb. 23, 1993, simply involves the sequential depression of the irrigation piston connected to the source of the hydrodissection fluid, release of the irrigation piston, which discontinues the flow of fluid, depression of the suction piston to effect aspiration of fluid from the operative field, and the repetition of the above sequence. As is thus evident, the sequential infusion of hydrodissection fluid, followed, thereafter, by suction through the same probe prolongs the operative procedures. To the extent that the flow of fluid is interrupted and/or a common channel of the same probe is used for both infusion and aspiration of fluid, the probe tip may become fouled with tissue fragments, blood and the like, thereby interrupting the fluid aspiration process and possibly requiring withdrawal of the probe from the operative field, its replacement and thereafter, the resumption of the operative procedure by reinsertion of the probe into the patient's body.
Without belaboring the foregoing, it is apparent that in order to maintain a clear channel in the hydrodissection (irrigation) probe, it is desirable (if not essential) to (a) maintain a continuous flow of hydrodissection fluid through the probe; and (b) effect aspiration of such fluid from the operative field through a separate probe, or separate channel within a common probe.
In the performance of a hydrodissection procedure of the type described above, it is highly desirable to perform concurrent infusion and aspiration of hydrodissection fluid. This continuous circulation of fluid within the operative field permits rapid clearing of the operative field of debris and, thus, facilitates the operative procedure.
In the event the hydrodissection procedure is performed utilizing a valve (i.e. trumpet valve), concurrent infusion and aspiration of fluid is not readily possible insofar as a common channel, within the valve body, connects each of the valve chambers to one another, and when both plungers are concurrently depressed, the irrigant will begin to flow through the valve body and at the same time a negative pressure is exerted upon the valve body in proximity to the common channel. Accordingly, irrigation fluid will be diverted from flowing into the probe tip by such negative pressure, resulting in it being simply cycled through the valve from the reservoir containing the hydrodissection fluid into the reservoir (fluid trap) associated with suction. The versatility afforded by the design of the trumpet valve has up to now prevented the effective concurrent infusion and aspiration of hydrodissection fluid due to a design limitation inherent in the construction of the valve body. Accordingly, there exists a continuing need to enhance both the versatility of a (trumpet) valve along with its ability to concurrently irrigate and aspirate fluid from an operative field.